assign printf format attribute to log_callback
Let the compiler detect and flag improper log messages at compile time.
BUG=chromium-os:34226
TEST=libevdev and cmt build clean
Change-Id: Ic339374361ab8bac7badc272e5dd33f9c8904ba6
Reviewed-on: https://gerrit.chromium.org/gerrit/32546
Reviewed-by: Andrew de los Reyes <adlr@chromium.org>
Commit-Ready: Daniel Kurtz <djkurtz@chromium.org>
Reviewed-by: Daniel Kurtz <djkurtz@chromium.org>
Tested-by: Daniel Kurtz <djkurtz@chromium.org>
diff --git a/include/libevdev/libevdev.h b/include/libevdev/libevdev.h
index 1cfe36c..891a423 100644
--- a/include/libevdev/libevdev.h
+++ b/include/libevdev/libevdev.h
@@ -19,7 +19,8 @@
#define NLONGS(x) (((x) + LONG_BITS - 1) / LONG_BITS)
typedef void (*syn_report_callback)(void*, EventStatePtr, struct timeval*);
-typedef void (*log_callback)(void*, int level, const char*, ...);
+typedef void (*log_callback)(void*, int level, const char*, ...)
+ __attribute__((format(printf, 3, 4)));
struct EvdevInfo_ {
struct input_id id;